Effect of Seed-coating Agents on Rice Seeds with Dehiscent Glumes

In order to improve the utilization efficiency of hybrid rice seeds, the effects of seed-coating agents on hybrid rice seeds with dehiscent glumes were investigated. Total six kinds of seed-coating agents were selected, i.e., 20.5% imidacloprid ·prochloraz FS, 30.5% imidacloprid oprochloraz FS, 23.0% thiamethoxam · hymexazol·prochloraz FS, Ruisheng WS, Shileshi FS and Liangdun FS, and their effects of seeds of Longliangyou Huazhan and T You 272 were investigated. The results showed that when the percentage of glume-dehiscent seeds reached 10%, 20.5% imidacloprid .prochloraz significantly improved the germination rate of Longliangyou Huazhan, which was 4.33% higher than that in the control group, and the seedling rate of Longliangyou Huazhan remained unchanged; 30.5% imidacloprid. prochloraz did not improved the germination rate of T You 272, but improved its seedling rate, which was 7.66% higher than that in the control group. When the percentage of glume-dehiscent seeds reached 20%, 20.5% imidacloprid ·prochloraz and 30.5% imidacloprid.prochloraz improved the germination rate of T You 272 by 3.50% and 4.83%, respectively, and its seedling rate did not decline. In conclusion, seed-coating agents have certain repair effect on glume-dehiscent rice seeds; 20.5% imidacloprid ·prochloraz and 30.5% imidacloprid ·prochloraz could improve the efficiency of Longliangyou Huazhan and T You 272 with small amounts of glume-dehiscent seeds.

Effect and Mechanism of Cold Tolerant Seed-Coating Agents on the Cold Tolerance of Early Indica Rice Seedlings

To better understand the effect and mechanism of cold tolerant seed-coating agents on the cold tolerance of rice seedlings, the physiological and biochemical effects of four cold tolerant seed-coating agents （HET, YKJ, YKZYJ, and the ABA seed coating agents） on two early indica rice varieties were studied under chilling stress. The results showed that the rice seedlings treated with cold tolerant seed-coating agents under chilling stress maintained dramatically higher root vigor, POD, CAT and SOD activities, and chlorophyll content, had lower MDA content and electrolyte leakage, and accumulated more soluble sugar and free proline, when compared with the control without the treatment, and finally showed lower plant injury rate. It was indicated that the cold tolerant seed coating agent improved the ability of rice seedlings in resisting to chilling stress. YKZYJ was ranked the first in terms of the efficiency in cold tolerance among the four cold tolerant seed-coating agents tested.

Can soil remediation agents synergistically mitigate rice Cd content and CH_(4)emission from karst paddies?

Rice(Oryza sativa L.)paddies are increasingly threatened by cadmium(Cd)pollution,and potentially serve as CH_(4)emitters to the atmosphere.Remediation agents widely mitigate Cd pollution in paddy soil,however,we know little about their regulations on CH_(4)emission.Here,via adding biochar(B),sulfhydryl-modified palygorskite(SMP),and selenium foliar fertilizer(SFF),we conducted a pot experiment to investigate soil and rice Cd contents together with in-situ CH_(4)f luxes.Compared to CK,the addition of SMP,SFF,and B-SMP reduced Cd in brown rice by 25%to 50%,25%,and 50%to 75%,respectively.Agents 7%B,7%B-0.01%SMP,and SFF reduced CH_(4)emissions by 8.46%,5.30%,and 4.11%,respectively.CH_(4)emission increased gradually along the growing season,with the cumulative CH_(4)fluxes ranging between 338.82 and 619.13 kg hm^(-2).Our results highlight that mixed 7%B-0.01%SMP and SFF showed collaborative eff ects on Cd remediation and CH_(4)emission.This study reveals the feasibility of reducing Cd pollution and CH_(4)emission in karst rice paddies,which hopes to supplement the knowledge of collaborative controls on soil remediation and carbon emission.

Effects of 4 Types of Remediation Agents on Reducing Cd Contents in Soil and Rice on Cd-contaminated Farmland

A field experiment was carried out in Cd-contaminated rice fields in a county of Hengyang to explore the effects of different types of remediation agents on the contents of soil available Cd and rice Cd,and rice yield by using one rice variety Longliangyouhuazhan,and 4 kinds of remediation agents:DG foliar control agent,SMA microbial inoculant,XFJ organic fertilizer and LXM calcium-and silicon-based passivator as test materials.The results showed that compared with CK,after applying DG foliar control agent,soil available Cd content increased rather than decreased,whereas rice Cd content decreased,not reaching a significant level.When applied with SMA microbial inoculant,soil pH value,soil available Cd and rice Cd contents showed a downward then upward trend with the increase of its application rates.Between 3 levels of SMA treatments,the content of soil available Cd in SMA2 was the lowest,decreased by 8.59%in comparison with CK,contrarily,two other SMA treatments were increasing instead of decreasing in the content of soil available Cd.The application of XFJ organic fertilizer and LXM calcium-and silicon-based passivator increased soil pH value,and reduced soil available Cd and rice Cd contents;the contents of soil available Cd and rice Cd decreased with their application rates increasing.Compared with CK,XFJ3 reduced soil available Cd content by 9.40%,and significantly reduced rice Cd content by 57.28%.In LXM3 treatment,soil available Cd content reduced by 14.57%,rice Cd content was 71.57%lower than CK,reaching the lowest level.In general,LXM calcium-and silicon-based passivator had the best Cd reduction effect,with the optimal application amount of 6000 kg/hm^(2).

Effects of Microbial Agents on Kitchen Waste and Rice Straw Composting

In order to clarify the influence of microbial agents on kitchen waste and rice straw composting, an aerobic composting experiment was conducted by setting three kinds of combined bacterial agents to study the temperature change in the composting, and pH value, nutrient contents, C/N and heavy metal content after composting through. The three kinds of combined bacterial agents were as follows:B1 with effective strains: Bacillus subtilis, yeast and Trichoderma sp.;B2 with effective strains: Bacillus amyloliquefaciens, yeast and lactic acid bacteria;B3 with effective strains: Bacillus subtilis, yeast and lactic acid bacteria. Results showed that the addition of microbial agents had signifcant effects on temperature change,nitrogen and phosphorus content and C/N of the compost. T1, T2, and T3 treatments lasted for 8, 5 and 4 d in the thermophilic phase above 60℃, respectively. The total nitrogen content of each treatment was 14.90, 15.50 and 13.80 g/kg respectively after composting. The total phosphorus content of each treatment was 4.87, 4.17 and 3.70g/kg respectively at the end of composting. The C/N of each treatment was 20.94,22.63, and 22.65 respectively at the end of composting. The application effect of B1bacteria agent on the composting of kitchen waste and rice straw was better.

Effects of Different Seed Coating Agents on the Quality of"Grey-matter"Hybrid Rice Seeds

[Objectives]This study was conducted to select suitable mixed seed coating agents for improving the quality of"grey-matter"hybrid rice seeds.[Methods]Three different mixed seed coating agents(A,B,C)were used to coat the seeds of two varieties(Taiyou 390 and Zhenliangyou 8612)of hybrid rice with different"grey-matter"content(5%,15%,25%),and the results were investigated and compared.[Results]The combinations of treatment B(seed coating agent A+Linong)and treatment C(Manshijin+seed coating agent A)could significantly improve indexes including seed germination potential,germination rate,seed vigor,seedling height,fibrous roots and fresh weight of the two varieties with a"grey-matter"content greater than 15%,but had no significant effects on main root length,dry weight,leaf number and tiller number,and the effects of treatment B was better than those of treatment C.That is to say,mixed seed coating agent B(seed coating agent A+Linong)was suitable for use as a seed coating agent to improve the quality of"grey-matter"seeds.[Conclusions]This study provides a reference plan for the safe use of mixed seed batches with"grey-matter"deterioration.

Analyzing the Roles of Agricultural Extension Agents in Hybrid Rice Technology Decision-Making Process of Farmers

The study determined the roles of agricultural extension in hybrid rice technology decision-making process by extension agents,Nay Pyi Taw,Myanmar.The specific objectives were:to study personal characteristics of agricultural extension agents,experiences and their roles,to identify extension agents’opinion on hybrid rice technology decision-making process,and to determine relationship between the roles of agricultural extension agents and decision-making process of hybrid rice production.One hundred and eight extension agents were collected who were working in Department of Agriculture,Nay Pyi Taw area and surveyed and interviewed by questionnaires.The study revealed that majority of agricultural extension agents(65.7%)were female staffs and most of extension agents(40.7%)were under 30 years as young staffs.Majority of extension agents(81.5%)were educated only Agri-Diploma.More than half(54.6%)had one to five-year experiences in employment and 58.3%had no hybrid rice training experience and source of information regarding the hybrid rice production was received 63.9%from Department of Agriculture(DOA).Study found that there was highly significant relationship between most of the roles of agricultural extension agents and hybrid rice technology decision-making process of stages 4 and 5.And then most of the extension agents’roles singnificantly related with stage 2 except role of conducting introduction of hybrid seeds and distribution through by Seed Co.Ltds which was highly significant.Beside,most of the roles of extension agents significantly related with stage 3.However stages 1 and 6 were no singnificantly related.Finally above all,a well structure seed business,Good Agricultural Practices and farm level mechanization and quality extension service are very important to increase the adoption of hybrid rice in Myanmar.

Compound Microbial Agent Improves Soil Redox Status to Reduce Methane Emissions from Paddy Fields

Paddy fields are considered a major source of methane(CH_4)emissions.Aerobic irrigation methods have proven to be efficacious in mitigating CH_4 emissions in paddy cultivation.The promising role of compound microbial agents in refining the rhizospheric ecosystem suggests their potential as novel agents in reducing CH_4 emissions from paddy fields.To explore a new method of using compound microbial agents to reduce CH_4 emissions,we conducted pot and field experiments over the period of 2022-2023.We measured CH_4 flux,the redox potential(Eh)of the soil,the concentration of dissolved oxygen(DO)in the floodwater,and the gene abundance of both methanogens(mcr A)and methanotrophs(pmo A).The results showed that the application of the compound microbial agent led to a significant increase in the DO levels within the floodwater and an increase of 9.26%to 35.01%in the Eh of the tillage soil.Furthermore,the abundance of pmo A increased by 31.20%,while the mcr A/pmo A ratio decreased by 25.96%at the maximum tillering stage.Applying 45-75 kg/hm^(2) of the compound microbial agent before transplanting resulted in a reduction of cumulative CH_4 emissions from paddy fields by 17.49%in single-cropped rice and 43.54%to 50.27%in double-cropped late rice during the tillering stage.Correlation analysis indicated that CH_4 flux was significantly negatively correlated with pmo A gene abundance and soil Eh,and positively related to the mcr A/pmo A ratio.Additionally,soil Eh was significantly positively correlated with pmo A gene abundance,suggesting that paddy soil Eh indirectly affected CH_4 flux by influencing the pmo A gene abundance.In conclusion,the pre-planting application of the compound microbial agent at a rate of 45-75 kg/hm^(2) can enhance the Eh in the rhizosphere and increase the abundance of the pmo A gene,thereby reducing CH_4 emissions from paddy fields during the tillering stage of rice growth.

The effect of different staining agents on the staining intensity of esterase isozyme zymogram of rice

Almost all previous reports on plant esterase(EST)isoenzyme analysis appeared to have ac-cepted that the relative staining strength(RSS)ofelectrophoretical bands represented the relative ac-tivities and contents of the correspondingisoenzymes.Nevertheless,we found in studyingthat the RSS changed with different staining

Application Effects of Ultra-fine Powder Shaped Maize Seed Coating Agent in Spring Sowing areas in northeast China

The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved around 5% and the num- ber of root increased by 4% in the treatments with ultra-fine powder shaped maize seed coating agent compared with the control group without seed coating. What＇s more, the treatments with ultra-fine powder shaped maize seed coating agent took advantages in terms of fresh weight of seeding, stem diameter, and dry weight. It is notable that control effects on underground insects performed the best, with per- centage over 94%, which is more excellent relative to other agents in markets. Therefore, ultra-fine powder shaped maize seed coating agent can be widely applied in spring sowing areas in northeast China, without side effects.

The Control Effect of Prevention and Control Technology Combination against Southern Rice Black-Streaked Dwarf Disease

Objective] This study aimed to explore a better prevention and control technology combination against southern rice black-streaked dwarf disease. [Method] The control effects of seed dressing, antiviral agents and fly net along with 25%pymetrozine against southern rice black streaked dwarf disease were determined. [Result] When the seeds were dressed with 60% imidacloprid （FS, 2 g a.i./kg）, and the rice seedlings were sprayed once with 25% pymetrozine （WP, 360 g/hm2） 10 d before the transplanting and sprayed twice with 30% Dufulin （WP, 800×） at three-leaf stage and 7 d after the transplanting respectively, the control efficiency reached 88.05%. When fly net and pesticides were applied simultaneously, the fly net was lifted and 25% pymetrozine （WP） was spayed once on the rice seedlings at six-leaf stage and the seedlings were hardened for 3 d and sprayed once with 25%pymetrozine （WP） 10 d after the transplanting, the control efficiency reached 80.50%. [Conclusion] Seed dressing or applying antiviral agents alone can not better control diseases. The southern rice black-streaked dwarf disease can be better con-trol ed by seed dressing, along with spraying of planthopper-kil ing agents at two-leaf stage, 3 d before the transplanting and 7 d after the transplanting, respectively. If condition al ow, fly net can be instal ed to achieve better control effect.

Anticancer Activities of Plant Secondary Metabolites:Rice Callus Suspension Culture as a New Paradigm

Plant natural products including alkaloids,polyphenols,terpenoids and flavonoids have been reported to exert anticancer activity by targeting various metabolic pathways.The biological pathways regulated by plant products can serve as novel drug targets.Plant natural compounds or their derivatives used for cancer treatment and some novel plant-based compounds which are used in clinical trials were discussed.Callus suspension culture with secondary metabolites can provide a continuous source of plant pharmaceuticals without time and space limitations.Previous research has shown that rice callus suspension culture can kill>95%cancer cells with no significant effect on the growth of normal cells.The role of candidate genes and metabolites which are likely to be involved in the process and their potential to serve as anticancer and anti-inflammatory agents were discussed.Large scale production of plant callus suspension culture and its constituents can be achieved using elicitors which enhance specific secondary metabolites combined with bioprocess technology.

天津地区水稻恶苗病防治药剂筛选试验

天津市优质农产品开发示范中心开展水稻恶苗病防治药剂筛选试验。试验表明,17%杀螟·乙蒜素+80%乙蒜素对恶苗病的防效达100%,节本高效;经1万hm2以上生产实践检验,1 kg带菌种子用17%杀螟·乙蒜素5 g+80%乙蒜素0.6 ml浸种处理7~8 d,种水比1:1.1~1.2,恶苗病病株最少,仅个别种植户因操作不当本田零星出现恶苗病。

基于微生物组学分析揭示土壤调理剂促进水稻增产的机制

为了解析土壤调理剂促进水稻增产的机制,开展施用土壤调理剂(TS)和未施用土壤调理剂(CS)的大田试验,通过分析土壤养分指标探究调理剂对土壤理化性质的改善效果,借助高通量测序技术测定施用调理剂对土壤微生物群落结构的影响。结果表明:施用专用调理剂(碱性)后,(1)水稻单产增加810.15 kg·hm^(-2)(6.83%);(2)土壤养分状况得到明显改善,土壤pH和交换性钙离子含量显著提高;(3)地杆菌科、噬几丁质科、亚硝化单胞菌科、Nitrososphaeraceae、假球壳科和Ustilaginaceae的相对丰度明显提高;(4)相对丰度前30的科中,土壤p H与噬几丁质科、黄色杆菌科、Bacteroidetes_vadinHA17、嘉利翁氏菌科、葫芦腔菌科呈显著负相关,与Nitrososphaeraceae和Ustilaginaceae呈显著正相关;土壤交换性钙离子与黄色杆菌科、Bacteroidetes_vadinHA17和地根壶菌科呈显著负相关,与Nitrososphaeraceae和Ustilaginaceae呈显著正相关。综上所述,施用专用土壤调理剂(碱性)能改善土壤理化性质和微生物群落结构,从而有利于水稻干物质积累和产量提升。

优化基肥和提苗肥对烤烟生长及品质的影响

【目的】明确基肥中添加微生物菌剂和提苗肥中添加尿素对稻茬烤烟促早生快发的效果。【方法】以云烟87为材料,采用双因素试验,设计基肥施用方法(基肥中未添加微生物菌剂、基肥中添加微生物菌剂),以及提苗肥施用方法(单施烟草专用提苗肥、单施尿素、烟草专用提苗肥和尿素混施),研究了微生物菌剂、优化提苗肥及其互作对烤烟的农艺性状、干物质量、养分积累,以及烟叶的物理性状、化学成分、感官质量和经济性状的影响。【结果】基肥中添加微生物菌剂和烟草专用提苗肥配施尿素可增加最大烟叶面积,提高烤烟干物质量和氮、磷、钾养分积累量,提高烟叶物理性状指数、化学成分可用性指数、感官质量和经济效果指数,增加烟叶产值,但施用尿素作提苗肥可提高叶片厚度、叶面积质量和烟碱含量。优化基肥添加微生物菌剂和提苗肥处理烟叶的物理性状指数、化学成分可用性指数、感官质量和经济效果指数较传统施肥方法分别提高2.85%,18.48%,9.79%和3.76%。【结论】稻茬烤烟穴施基肥中添加微生物菌剂、专用提苗肥中适量配施尿素可以作为促进烤烟早生快发的一项技术措施,但必须控制施氮总量。

药剂拌种对稻麦轮作中迟播小麦生长及产量的影响

为探讨药剂拌种对沿淮地区迟播小麦的壮苗效应及产量的影响,以准麦33为试验材料,设置3个不同药剂拌种处理和1个不拌种对照处理,调查分析了对小麦田间生长及产量影响.结果表明:与不拌种相比,药剂A1及A2可以降低小麦第1叶出叶高度及第1、2节间长度,从而使株高降低;同时可以促进生物量积累,增强小麦分能力,增加有效穗数.其中A1药剂组的千粒重性状表现较好,产量增加显著;A3药剂组增加了小麦节间长度及株高,营养生长旺盛,分能力较强,有效穗数增加,产量得到提高,但每穗粒数有所降低.综上表明,药剂拌种具有壮苗效应、促进分藥,促进小麦稳产增产,其中药剂A1表现最优.

不同生物菌剂对水稻秧苗素质及产量品质的影响

试验采用完全随机区组设计,共6个处理(含CK),探讨了不同生物菌剂对龙粳31秧苗素质、田间防效及产量、品质的影响。结果表明:应用NK3-4生物菌剂的处理秧苗素质表现最佳,叶龄、根长、根数、茎基宽、百株地上干重分别较CK增加了0.3叶、0.7 cm、0.3条、0.3 cm、0.3 g;NK3-4生物菌剂田间防效达到36.6%;应用三环唑制剂的处理产量最高,其次是NK3-4生物菌剂处理,与CK相比较分别增产29.4%、21.2%。根据促进水稻秧苗素质、稻瘟病防治以及水稻产量、品质的综合测评,自主研发的NK3-4生物菌剂表现优于其它生物菌剂,可作为防病促生菌进一步研究,为NK3-4生物菌剂后续开发成生物肥料、生防菌剂提供理论基础。

不同钝化产品对水稻生产中镉、铅、砷的钝化效果

采用田间试验,持续2年(2021—2022年)研究了市售6种钝化剂不同施用量(0、2 250、4 500、6 750 kg·hm^(-2))对土壤中镉(Cd)、铅(Pb)、砷(As)有效态含量,土壤pH值,及稻米Cd、Pb、As含量的影响。结果表明,选择适宜用量的钝化剂可显著(P<0.05)提高土壤pH值,降低土壤有效态Cd、Pb、As含量。其中,施用6 750 kg·hm^(-2)长效型钝化剂的效果在2021年最优,土壤pH值由5.00提高至6.98,土壤有效态Cd、Pb含量分别显著降低82.2%和98.6%。此外,长效型钝化剂在4 500 kg·hm^(-2)用量下,第二年的稻米镉含量仍可显著降低90.8%。综上,在对比的6种钝化剂中,长效型钝化剂阻控水稻籽粒Cd富集的效果和持效性最优,推测与其碳酸钙含量较高有关。

水肥和钝化剂阻控水稻吸收镉机制的研究进展

镉(Cd)污染严重威胁生态环境,Cd污染水稻会对人体健康造成极大影响,防控水稻Cd污染迫在眉睫,也是当前研究的热点之一。水肥管理和施用钝化剂是目前治理水稻Cd污染有效且主流的措施。本文综述了水稻Cd污染的现状,及水肥管理和钝化剂施用治理Cd污染的作用机制,即水肥管理主要通过吸附沉淀作用和离子竞争作用阻控,钝化剂主要通过共沉淀、络合作用、吸附和离子交换作用以及氧化还原作用进行阻控。分析了治理后的土壤环境(土壤理化性质、土壤微生物和土壤酶)变化,展望了今后的研究方向。

不同腐熟剂对麦秸腐解率与稻田水环境的影响

为探明麦秸还田条件下施用腐熟剂对秸秆腐解效果、稻田水环境风险的影响,选用4种腐熟剂(标识为DA1、DA2、DA3和DA4)进行水稻季麦秸腐解试验。结果表明,施用4种腐熟剂均加快还田后4周内秸秆腐解速度,其中,还田后2周为麦秸快速腐解期,且腐熟剂DA3和DA4促进麦秸腐解的效果更佳,腐解率达36.5%~37.4%,较麦秸还田无腐熟剂处理(CFS)增加了5.1~6.0个百分点。与CFS处理相比,4种腐熟剂处理提高了麦秸还田后3周内田面水化学需氧量(COD)及氮磷含量,增加了水稻生长初期的水环境风险。其中,DA2、DA3和DA4这3种腐熟剂处理后3周内田面水环境风险相对较高,而DA1与CFS处理间水环境风险差异不显著。可见,稻田施用腐熟剂会加速麦秸腐解,同时会增加水稻生长初期的水环境风险,建议南方水网区水稻季谨慎施用腐熟剂。